Image Processing Apparatus and Image Processing Method for Displaying a Focused Portion with Emphasis on an Image

1. An image processing apparatus, comprising: a focused area judgment unit configured to judge a focused area in target image data; a distribution information generation unit configured to generate distribution information of an edge evaluation value with the focused area judged by the focused area judgment unit as a target, wherein the distribution information generation unit generates the distribution information of the edge evaluation value using a contrast differential obtained as a derivative value of a luminance between adjacent pixel data as the edge evaluation value; a threshold value setting unit configured to variably set a threshold value used for judging an emphasis display portion using the distribution information generated by the distribution information generation unit; and a display data generation unit configured to select an emphasis display portion in the image data using the threshold value set by the threshold value setting unit and generate display data for displaying the selected portion with emphasis.

2. The image processing apparatus according to claim 1 , wherein the display data generation unit generates display data for displaying with emphasis a portion inside the focused area, that has been selected based on a result of a comparison with the threshold value, within the image data.

3. The image processing apparatus according to claim 1 , wherein the threshold value setting unit sets emphasis effect amount information corresponding to the threshold value, and wherein the display data generation unit uses the emphasis effect amount information in a pixel data conversion operation for display with emphasis.

4. The image processing apparatus according to claim 3 , wherein the display data generation unit sets a luminance value of the emphasis display portion using the emphasis effect amount information.

5. The image processing apparatus according to claim 1 , wherein the threshold value setting unit sets, based on the distribution information generated by the distribution information generation unit, the threshold value using the edge evaluation value with which an accumulative pixel count from a distribution high-order side becomes a set pixel count ratio.

6. The image processing apparatus according to claim 1 , wherein the threshold value setting unit provides an upper limit and a lower limit to the threshold value to be set.

7. An image processing method, comprising: judging a focused area in target image data; generating distribution information of an edge evaluation value with the judged focused area as a target, wherein the distribution information of the edge evaluation value is generated using a contrast differential obtained as a derivative value of a luminance between adjacent pixel data as the edge evaluation value; variably setting a threshold value used for judging an emphasis display portion using the generated distribution information; and selecting an emphasis display portion in the image data using the set threshold value and generating display data for displaying the selected portion with emphasis.

8. A non-transitory computer readable medium having stored thereon, a set of computer-executable instructions that causes an operational processing apparatus to execute the processing of: judging a focused area in target image data; generating distribution information of an edge evaluation value with the judged focused area as a target, wherein the distribution information of the edge evaluation value is generated using a contrast differential obtained as a derivative value of a luminance between adjacent pixel data as the edge evaluation value; variably setting a threshold value used for judging an emphasis display portion using the generated distribution information; and selecting an emphasis display portion in the image data using the set threshold value and generating display data for displaying the selected portion with emphasis.